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CASE STUDY 5: Loughborough Endowed Schools

	Location		Loughborough, Leicestershire
	Duration		12 Weeks
	Client		Loughborough Endowed Schools
	Scope of Works		Installation of: Fiber Optic Backbone Cabling Server Cabinets & Accessories Fiber Optic Testing & Certification to 1000BASE-SX (Gigabit Ethernet) OTDR Testing Video Fiber Endface Inspection 25-Year Warranty.
	Project Focus
	The schools IT department required their Fiber Optic backbone cabling testing for its suitability to support 1000Base-SX Gigabit Ethernet prior to installing new HP Core switches. No previous Fiber optic test records existed so the cables capability to support gigabit Ethernet across the backbone could not be established without testing the existing cabling.
	We first had to undertook a site audit to establish the routing and termination points around the site which has in excess of 30 remote cabinets which connect to the main communication room within Network Services IT Dept. It soon became apparent that most of the cabling was OM1 62.5/125um type multimode Fiber, much of which would not support 1000BASE –SX due to the length restrictions of this type of cable. Other serious problems were discovered included including poorly jointed cabling, cabling being extended to cover other department by simply running new lengths from one department to another then using Fiber patch leads to extend the run. The result was unacceptable losses when we commenced testing the existing Fiber Optic Cabling from end to end with worst case losses of 15Db. An OTDR was used to test the losses by sending a trace along the entire length of the link which recorded each individual event and recorded the losses along the entire length of the cable. Due to the amount of cables joined by Fiber patch cords and core size mismatches high losses were recorded in more than 75% of the cabling tested.
	We further tested each link using a Fluke Certification tester which will simply give a pass or fail when testing Fiber optic cabling to a a standard which in this case was 1000BASE-SX. (1000mbps) Which has a maximum loss of 3.4 Db as opposed to IIdB which would have been the maximum loss for use with 100BASE-FX (100mbps) Following the problems discovered a decision was made to upgrade the entire Fiber Optic backbone cabling and install OM3 50/125um multimode cabling which will support 1000BASE-SX transmission up to 550m. The new cabling was installed over a 12 week period with most of the cabling being physically installed to each remote communication cabinet in one individual lenghth throughout the summer holidays. A fusion splicer was used to terminate factory polished pigtail connectors onto the new cables ensuring minimum losses, and a far superior finish compared to other methods of termination including hand polishing & crimping connectors etc… Testing & Certification of the Fiber optic cabling was carried out using a Fluke certification tester, OTDR & a Video probe which is used to capture endface images of each Fiber core installed. These captured images form part of our testing criteria and we believe, provides the client with the assurance of a quality installation.
	Every cable installed was tested using an OTDR to provide a trace of the cable showing losses incurred at each connector and showing the losses along the entire length from end to end. The cabling was further tested using a Fluke Certification tester to certify the cablings ability to meet 1000BASE-SX (Gigabit) test standard. Following the successful installation and testing of the new Fiber Optic backbone cabling a full comprehensive set of test results was handed over to the client. Telephone services were provided by installing a 50 pair voice backbone cable to connect the new Chemistry building to the schools PABX telephone system. Following the successful upgrade of the backbone cabling the new switches gigabit switches have now been installed and resulted in a vast improvement to the network speed and stability enabling the IT to move forward with the confidence the infrastructure now in place forms a solid foundation to build on.